Mitochondria-targeted antioxidant protects against irradiation-induced salivary gland hypofunction

A severe consequence of radiation therapy in patients with head and neck cancer is persistent salivary gland hypofunction which causes xerostomia and oral infections. We previously showed that irradiation (IR) of salivary glands in mice triggers initial transient increases in mitochondrial reactive oxygen species (ROSmt), mitochondrial [Ca2+] ([Ca2+]mt), and activated caspase-3 in acinar cells. In contrast, loss of salivary secretion is persistent. Herein we assessed the role of ROSmt in radiation-induced irreversible loss of salivary gland function. We report that treatment of mice with the mitochondrial-targeted antioxidant, MitoTEMPO, resulted in almost complete protection of salivary gland secretion following either single (15 Gy) or fractionated (5 × 3 Gy) doses of irradiation. Salivary gland cells isolated from MitoTEMPO-treated, irradiated, mice displayed significant attenuation of the initial increases in ROSmt, ([Ca2+]mt, and activated caspase-3 as compared to cells from irradiated, but untreated, animals. Importantly, MitoTEMPO treatment prevented radiation-induced decrease in STIM1, consequently protecting store-operated Ca2+ entry which is critical for saliva secretion. Together, these findings identify the initial increase in ROSmt, that is induced by irradiation, as a critical driver of persistent salivary gland hypofunction. We suggest that the mitochondrially targeted antioxidant, MitoTEMPO, can be potentially important in preventing IR-induced salivary gland dysfunction.

Phylogenomics of Tick Inward Rectifier Potassium Channels and Their Potential as Targets to Innovate Control Technologies

This study was conducted to enhance the identification of novel targets to develop acaricides that can be used to advance integrated tick-borne disease management. Drivers for the emergence and re-emergence of tick-borne diseases affecting humans, livestock, and other domestic animals in many parts of the world include the increased abundance and expanded geographic distribution of tick species that vector pathogens. The evolution of resistance to acaricides among some of the most important tick vector species highlights the vulnerability of relying on chemical treatments for tick control to mitigate the health burden of tick-borne diseases. The involvement of inward rectifier potassium (Kir) channels in homeostasis, diuresis, and salivary gland secretion in ticks and other pests identified them as attractive targets to develop novel acaricides. However, few studies exist on the molecular characteristics of Kir channels in ticks. This bioinformatic analysis described Kir channels in 20 species of hard and soft ticks. Summarizing relevant investigations on Kir channel function in invertebrate pests allowed the phylogenomic study of this class of ion channels in ticks. How this information can be adapted to innovate tick control technologies is discussed.

Justification of the effectiveness of hirudotherapy in dentistry

This article provides a systematic review of studies on the composition of leech saliva secretions, the method of hirudotherapy, and the results of hirudotherapy in complex treatment. The following databases were used to search for the study: Scopus, Web of Science, MedLine, and Global Health. When using known methods of treatment, there is often no stability of results, this is explained by the search for new drugs and methods for treating periodontitis. It is known that the secret of the salivary glands of the medical leech contains more than 100 biologically active substances. The therapeutic effect of hirudotherapy is associated with the mechanical discharge of blood flow and the action of a complex salivary gland secretion of a medical leech. The molecules that exist in leech saliva and are the most studied to date include active substances such as hyaluronidase, hirudin, Kalin, destabilase, bdellins, histamine-like substances, hirustazine, factor XA inhibitor, and collagenase. It is scientifically proven that hirudotherapy leads to a significant improvement in the clinical condition of periodontal tissues, is simple, accessible, and can be recommended for use in the practice of periodontists.

SIDS: EPIDEMIOLOGY, INFANT PHYSIOLOGY AND SALIVA ASPIRATION

A sudden infant death syndrome (SIDS) is diagnosed in the case of a sudden and unexpected death of an infant during sleep and where an autopsy shows no obvious pathological lesions or injuries. Although literature indicates a wide range of risk factors, there is no single opinion on the specific cause of SIDS. This paper describes a study of 191 infant deaths in which the State Forensic Medicine Service established 29 SIDS cases. Microscopical and histological results of samples taken from sections of the respiratory system reveal serous fluid in the alveoli and change specific to asphyxia in all autopsy cases of infants diagnosed with SIDS. The risk of SIDS is highest in infants aged 1–4 months. Salivary gland secretion increases with the development of infant physiology, and this increase coincides with infant teething. However, in this phase, an infant’s swallowing reflex is still to form completely. Findings suggest that the serous fluid found in the alveoli was from the salivary glands, and thus, saliva aspiration may be associated with infant deaths due to SIDS.